Direct agent jar link at "Running the agents without the service wrapper" returned Internal Server Error

Problem Description
Some of the administrator would like to run agent without service wrapper from Adding agent panel in Bamboo administration. However it wouldn't work as the link would only return Internal Server Error page. Despite of that, you could still access the bamboo-agent-x.x.x.jar file through file directory in $BAMBOO-INSTALL/atlassian-bamboo/admin/agent. This issue didn't occur in Bamboo 4.4.5.

Steps to replicate

1. Navigate to Bamboo Admin >> Agents
2. If you haven't enable Remote agent capability, enable it
3. Navigate to Install Remote Agent
4. Under Running the agents without the service wrapper click on the bamboo-agent-x.x.x.jar

Workaround
Access the jar file through file directory, to be exact, it's inside $BAMBOO-INSTALL/atlassian-bamboo/admin/agent directory.